NITROX CERTIFICATION PROTOCOLS - REAL WORLD

[BRT]

Yes, of course, but the OP was not talking about his own tank or any other regular customer. He mentions "instructors and DMs" specifically. If they were all employees of the shop then they likely were loading the tanks before the dives.

Yep, but not checking the O2 content.

 

[360GUY]

Just to be clear, In Cozumel, as many of you know, there are hotels lined up along the banks of the ocean. For 3 days in a row, morning and afternoon, it was myself and 3 or 4 other guys, who were vactioning in Cozumel. They also happened to be very experienced. Each morning, and then again, each afternoon, I'd be on the boat first, at the marina. I'd watch and help load the talks and other gear onto the boat. We would then take off with myself, the DM from the Dive shop, and the boat captain. We'd then pick up the other guys, at their hotel docks. And then we'd head for the dive localtion.

I don't feel the need to mention the name of the dive shop, but they are a very reputable shop, with several boats. It was at the height of COVID, so there wasn't much business...Everyone was very professional and concerned about safety and protocol, and at the time, I wasn't EANx certified, so I had no idea what the methodology was. It was only when I was being trained, that I recalled, these dive buddies of mine (All DMs and instructors), did not teat any of their tanks...And they dove with nitrox day after day...

...and so it goes. I will say, in closing, that I'm very encouraged by the rock-solid advice here, in this thread. I have no doubt now, as to the proper (and only truly safe) method of diving with nitrox; that being, to take responsibility for your own safety, dive, life!!!

Now, will someone please recommend and solid analyzer!!! Good God, it never ends!!! ))

 

[OrcasC205]

What about your local dive shops? I’ve gotten fills at places that analyze and require you to sign their log. Other shops analyze but don’t keep a log. One shop knew I had an analyzer at home and didn’t require me to analyze in the shop. I’m not sure if they have a log. This was a shop that knows me.

Our local dive shop requires every tank leaving the shop to be analyzed and logged by the customer -- yes, that includes air-filled tanks (aka EAN21). Our procedure is to log the exact percentage in the shop's log, but only to write the whole-number (e.g. 32) percentage on the tank sticker. At the dive site on the day of the dive we analyze again and write in the decimal value (e.g. 32.3), date and initial the tank.

When we travel we bring our own analyzer, but will use the boat's analyzer if it is easier. But every tank gets analyzed and labeled on the day of the dive -- we pack a roll of blue masking tape in case the tanks don't have stickers.

 

[Manatee Diver]

One thing I don't do is add a MOD, Date and Tester. I know the MODs in my head for the mixes I dive plus my computer handles that, I'm always the tester and the date is irrelevant to me.

I put the date, as in cave country I was trained that every tank should be tested the day you are diving it. So if I see a testing tape that doesn't have today's date, it gets peeled off and retested. I also put my initials, so on boats with lots of steel tanks they all look the same.

 

[Marie13]

I put the date, as in cave country I was trained that every tank should be tested the day you are diving it. So if I see a testing tape that doesn't have today's date, it gets peeled off and retested. I also put my initials, so on boats with lots of steel tanks they all look the same.

Different colored tape helps it stand out. I use a bit of hot pink duct tape.

 

[Manatee Diver]

Different colored tape helps it stand out. I use a bit of hot pink duct tape.

Once I run out of my current blue tape, I have a roll of yellow tape that I will be switching to.

 

[Brett Hatch]

You breathe the wrong gas, you die. Suck it up and analyze your gas, it's not hard. If for some reason it is hard, don't dive that day. Don't be an idiot, don't follow the crowd, don't breathe the wrong gas. You breathe the wrong gas, you die.

Edit to add: I do not always write everything down that I learned in class. I don't always analyze as I set up me gear (I do this probably less than half the time, honestly). But I always analyze the tank before I dive it, no matter who said what about it, and always write down at least the O2%, MOD, and date. As I set my gear up, I double-check that my computer matches what the sticker on the tank says.

 

[Capt Jim Wyatt]

There are shops that sell nitrox yet have no analyzer for the customer to use. I can think of one such shop in cave country.

 

[Divin'Papaw]

I put the date, as in cave country I was trained that every tank should be tested the day you are diving it. So if I see a testing tape that doesn't have today's date, it gets peeled off and retested. I also put my initials, so on boats with lots of steel tanks they all look the same.

I don’t see the need to test them day of use when they are my own tanks. Nothing wrong with it, I just don’t see the need. I test them once after filling and label them. As far as telling my tanks from others, my name is on the crown of all of my tanks.

 

[Wibble]

My technical instructor told me an interesting story.

He was on a dive boat for a week, all divers measured the nitrox the first 1-2 days and everything was ok, through this safety almost no one measured anymore (shallow dives, no deco).

However, my instructor measured each tank himself with his own meter. Between two dives something went wrong and during his measurement the tank showed 21%. He contacted the crew, but they said that this could not be, the compressor has just been revised. They have measured various bottles and found that all have displayed 21%.

I'd bet money that they knew perfectly well that they'd not pumped nitrox; just air. If they mix it, they'd have run out of O2.

Have heard tales of a tin of pure O2 as a result of a mix-up when blending. Would have been interesting at 30m/100'. Actually not at all; it would probably kill you.